Tubular electric furnace.



No. 7|5g5o7. Patented Dec. 9, |902..

4H. n; POTTER.

TusuLAn -Eu-:crnlc'funnnca (Appuw'ion med rgb. 7. 1902.

. l al man.)

#w @d m by 4A-MJ MQ/4Z@ m: Nonms Pneus co. Puovauzruo., msmucmu. n cvUNITED STATES PATENT OEE1cE.

HENRY NOEL POTTER, OF NEW' ROCHELLE, NEW YORK, ASSIGNOR TO GEORGEWESTINGHOUSE, OF PITTSBURG, PENNSYLVANIA.

TUBULAR ELECTRIC FU RNACE.

SPECIFICATION forming part of Letters Patent No, 715,507, dated December9, 1902. Application filed February 7I 1902. Serial No. 92,968. (Nomodel.)

To all whom t may concern:

Be it known that I, HENRY NOEL POTTER, a citizen of the United States,and a resident of New Rochelle, in the county of Westchester and Stateof New York, have invented certain new and useful Improvements inTubular Electric Furnaces, of which the following is a specification. Y

The present invention relates to improvements in electric furnaces, thespecial object being to protect such furnaces from the danger of saggingor warping out of shape under the influence of extremely hightemperature to which they are subjected when in operation.

It is found that a carbon-tube furnace is subject to such distortion ofshape under the influence of extreme heat, the carbon becoming plasticat the high temperature reached in the furnace, while other substances,such as magnesia, which are also used to form the body of such furnaces,are still more Asubject to distortion of shape under the influence ofheat.

The means which I disclose herein for preventing the sagging or warpingof the carbontube furnace consists of a series of carbon collarssurrounding and supporting the internal tube throughout its length, thecollars eX- tending from the tube at right angles thereto into a regionwhich is much cooler than that next to the tube. This construction doesnot interfere with the use of the usual jacket for the carbon tube,inasmuch as the carbon collars referred to extend through or into thejacket, as will be readily understood. I generally prefer to surroundthe entire structure, including the jacket and the collars, with anon-conductin g tube,as will appear farther on.

My invention will be clearly understood by reference to the accompanyingdrawings, in which- Figure l is a longitudinal section of a furnaceconstructed in accordance with my invention, and Fig. 2 is a transversesection along the line al) in Fig. l.

Referring to the drawings, l is a tube of carbon constituting the innertube of au electric furnace. The partsindicated bythe charactor 2 areparts of a jacketing material, such as magnesia, surrounding the tube,while the parts indicated by the character are collars of carbonarranged to surround the carbon tube land extend at right angles to thetube l through the j acketing material. The whole is then surrounded bya non-conducting tube 4, which may be of stoneware and which constitutes a jacket-wall and makes a smooth and even external surface for thefurnace.` The terminal construction of this tube is formed in anyconvenient way. I show, for example,

at each end a carbon terminal 6 in the form of acollar or ringsurrounding the tube l, and I place around each carbon terminal a metalterminal '7, which may be a split ring capable of being pressed againstthe terminal 6 and of pressing the said terminal in turn against thecarbon tube l, so as to make good electrical connection. Through themetal connections 7 7 connection is made with the external circuit.

Vthile I have described an electric furnace having a carbon tube as themost central body of the furnace, yet such a tube might be provided witha lining of maguesia or other suitable material, and the central tubeitself may be com posed wholly of some suitable material, such asmagnesia, and derive support from collars of carbon or other material inthe way indicated.

I claim as my inventionl. A tubular electric furnace having a tube ofcarbon, and surrounded at intervals along its length bysupporting-collars of carbon extending at right angles to the lsaidtube.

2. A tubular electric furnace having a tube of carbon surrounded byalternate collars of jacketing material, such as magnesia and carbon,the carbon collars extending through or into the jacketin g material,and the whole being surrounded by a finishing-tube.

3. A tubular electric furnace having a tube of carbon surrounded byalternate collars eX- tending at right angles to the tube, one set ofcollars being of j acketing material, such as magnesia, and the otherbeing carbon.

4. A tubular electric furnace having a tube ofl carbon surrounded bysupporting-collars of carbon extending at right angles thereto,

IOO

vrings of jacketing materiaLsuch as magnesia,

alternating with the carbon collars, and a tube or ring surrounding thedescribed structure.

5. A tubular electric furnace having a coudlietng-tube surrounded atintervals along its length by supporting-collars of carbon eX- tendingat right angles to the said tube.

Signed at New York, in the lcounty of New York and State of New York,this 5th day of February, A. D. 1902.

HENRY N OEL POTTER.

Witnesses:

WM. H. CAPEL, GEORGE H. STOCKBRIDGE.

